Raymarine linear drive autopilot install query

[solmaniac]

I have a used linear long drive Raymarine (m81132) that I had checked by a technician who tells me everything is working. So now I'm trying to figure out if it will fit on the boat with a solid install. After messing with it all day and concluding it could fit...barely...I still have a problem. The install guide says there cannot be more than 5 degrees vertical movement in the shaft while operating. Well...am I right assuming that is impossible if the rudder stock enters the boat at more than 5 degree angle? As the quadrant turns from center...it drops. If an autopilot drive shaft is attached to it...that also drops. Even if it had it's own arm from the rudder...the same thing would happen. Has anyone else encountered this issue?

[lateral]

No. You just have to mount the LA with the base plate in the same plane as that which the quadrant scribes with the right amount of offset to allow for the height of actuator arm off the base plate.
If you can't do this then fully retract the actuator and mount making sure the angle is <5
then when the arm extends the angle will be less as the arm lengthens.
Arm should be 90 deg to quadrant/lever at 0 deg rudder and arm parallel to rudder scribe arc plane. Follow the manual.
http://www.seatronic.no/pdf/LS/Linear_Drive.pdf

If your quadrant/lever doesn't scribe a lamina plane then its
loose on shaft.

[solmaniac]

That is the guide I am using. I can mount the drive end 90 degrees off the rudder amidship on the quadrant and 90 degrees off where the base plate is mounted...but as the rudder turns...the center of the quadrant drops because the rudder stock is not vertical. Are you saying if I mount the base plate at the same angle as the rudder stock turns the quadrant this wouldn't happen? Hmmm...I'll have to think about that...it does seem like that might be the answer. Could have a whole new space problem though.

[Blue Stocking]

Your problem is quite common on boats with inclined rudder posts. There is rarely adequate room to mount the drive athwartships and still be within the balljoint travel parameters. Mounting on the fore and aft centreline gets around this but requires more room. I have seen quite complex, split - the - angle-mounted bellcrank assemblies get around this problem. I have the same problem on Bluestocking because on the rise in her counter. Ended up going with ST4000 which actually, with her long straight keel, will hold a course in 30knot, even though she comes in at 22000+ lbs.

[wiekeith]

Originally Posted by solmaniac

That is the guide I am using. I can mount the drive end 90 degrees off the rudder amidship on the quadrant and 90 degrees off where the base plate is mounted...but as the rudder turns...the center of the quadrant drops because the rudder stock is not vertical. Are you saying if I mount the base plate at the same angle as the rudder stock turns the quadrant this wouldn't happen? Hmmm...I'll have to think about that...it does seem like that might be the answer. Could have a whole new space problem though.

Can you not still use the mounting position you've identified, and just tilt the base by the angle of the rudder stock with a wedge, or even a few washers underneath one side? I.e. if your stock is 10 deg from vertical, for example, you'll need to tilt the drive 10 deg off horizontal. Or have I misunderstood the problem?

[Gary Matthesen]

I installed a Raymarine linear drive below deck on a Catalina 36. As they shaft was vertical I made the mount horizontal. You would have to install a wedge if you follow a similar installation to mine, to be perpendicular to the shaft as others have outlined
It was necessary to add blocks to limit the rudder travel so as not to max out the excursion of the linear ram. Fortunately I do not like docks anyway and close quarters maneuvers. As a new owner I may never realize how much rudder control I lost, although I am finding out under power the boat will still spin rather quickly chasing a missed mooring attempt.
Not wanting to sacrifice the limited storage space in the stern, I elected to mount the ram inverted and athwart ship on the starboard side. It looked though, with the curvature of the hull, it would be a tight fit, if doable at all. Relocation of the cockpit drain hose was the first casualty of the installation. Needing a firm mounting location, I used a 2x6 rafter leftover from repairs on my garage roof from Hurricane Sandy, who also took my previous boat. Never lost power though!
I braced the 2x6 lengthwise between the stringers that support the lazarrett shelf. These were held in place by thin steel plates screwed to the 2x6 and the stringers on both ends, at the same height of the stringers to not interfere with replacement of the lazarette compartment boards. Naturally I was not as lucky to have everything line up for those 90 degree angles specified. With the addition of 2 more thickness of 2x6, all held together with 5 inch bolts, also capturing the rams mounting base, I got a horizontal ram angle to the Edson tiller arm. With the arm in place and a new 18 inch drill bit, I drilled through the cabin wall and into the pilot hole of the tiller. In this awkward position it was difficult to exert the pressure to drill. Once through the rudder post wall, I continued into the other side of the wall. With occasional checks of the color of the drilling dust, it finally turned from aluminum to brass. I took the tiller arm apart and drilled at home, much easier. The bit then produced “ribbons” of brass, rather then dust, indicating I just was unable to push hard enough in the confines of the aft cabin to really cut quickly.
Location of the control head was an unused spot on the helm Pod, but with limited space to snake wires through due to other instruments, I considered to mount it on the coaming on the starboard side. This was the location on my previous boat, and would be nicely accessible from the helm and the cockpit. It would also up higher were it would be less inclined to get a button bumped as had been past experience.
Deciding not to cut more holes in the boat yet, and unable to find a satisfactory exploded view of the Edson pedestal, I decided to do some “exploratory disassembly”. The compass came apart in the usual manner, remove the night light housing, then the stainless housing, 4 large screws were exposed. With these removed the compass came off easily and the pedestal nearly fell apart. Really easy stuff. I then had to rummage around, as being new in the boat it was hard to find a well stocked junk drawer for a thin snake line to drop down into the holes inside the aft cabin for snaking the “back bone” wiring.
A point of interest, in my rush to “fire up” the new toy, I connected a “spur wire” from the computer to the head directly to see if I could get things working. An error message said “No Pilot” Try as I might I could not get the system up. A call into Tech Support, informed me you must use the “back bone” wire between the computer spur wire and the control head spur wire. Don’t know what magic lies in that blue backbone wire, but it worked right off.
I considered the initial mounting more of a mock up, with plans to modify if necessary over the winter. I found it necessary right off to add an angle iron bracket for a more secure mount to the stringers from the 2x6. This worked well to hold things in alignment from the torque of the ram trying to twist the 2x6 mount. All was well with the mounting to go last summer from Oyster BayNY out to Martha’s Vineyard.
I hope this helps and encourages others to mount a below deck system on their boat. Really the worst part was the drilling!

[ramblinrod]

Originally Posted by solmaniac

That is the guide I am using. I can mount the drive end 90 degrees off the rudder amidship on the quadrant and 90 degrees off where the base plate is mounted...but as the rudder turns...the center of the quadrant drops because the rudder stock is not vertical. Are you saying if I mount the base plate at the same angle as the rudder stock turns the quadrant this wouldn't happen? Hmmm...I'll have to think about that...it does seem like that might be the answer. Could have a whole new space problem though.

Mount the base of the drive unit on a plate parallel with the quadrant angle.

The quadrant and drive unit arm are now on the same plane over the full travel, and the change in horizontal angle is zero.

Raymarine Certified Installer / Service Provider